Loom stop motion



Dec. 7, 1943. c. D. BROWN LOOM STOP MOTION Filed April 8, 1943 F. 3. INVENTOR.

C. D. BRowN ATTORNEY Patented Dec. 7, 1943 LOOM STOP MOTION Carl D. Brown, Hopedale, Mass, assignor to Draper Corporation, Hopedale, Mass, a corporation of Maine Application April 8, 1943, Serial No. 482,238

4 Claims. 139-375) The present invention relates generally to center fork stop motions and, as illustrated herein, relates more particularly to vibration preventing means for such stop motions.

In stop motions of the type to which my invention is applied, the actuating rod moves longitudinally and carries a lifting cam for lifting the filling fork when the rod moves in one direction. The lifting cam is provided with a stop shoulder which cooperates with the filling fork to prevent movement of the rod in the opposite direction in the event of filling failure. The actuating rod is subject to substantial vibration which under some conditions may be sufiicient to prevent proper action of the filling fork and thus permit movement of the rod even though there has been a filling failure.

An object of the present invention is to provide a center fork stop motion for looms wherein the above mentioned difiiculties will be overcome. To this end, and as illustrated, the actuating rod on which the lifting cam is mounted is provided with a member which is fixed to the actuating rod and has portions bearing against the lay and prevents vibration thereof during operation of the loom.

With the above and other objects in view, the invention will now be described with particular reference to the accompanying drawing which illustrates a preferred embodiment of the invention and in which:

Fig. l is a perspective view of a portion of a loom having the present invention applied thereto;

Fig. 2 is a view, partly in section, illustrating a preferred embodiment of the invention; and

Fig. 3 is a view in front elevation of the construction shown in Fig. 2.

The present invention is illustrated as applied to a center fork stop motion for looms of the type disclosed in United States Letters Patent No. 1,865,930 granted July 5, 1932 on an application filed in the name of Verner Lindsjo. In the drawing, only a portion of a lay beam ll! of the usual loom is shown, and the parts of the loom not shown may be of conventional construction and form no part of the present invention.

The presence or absence of a filling thread is detected by a filling fork I2 and upon detection by the fork of the absence of a filling thread, the stop motion disclosed in the aforesaid Letters Patent is actuated to effect stopping of the loom. The filling fork I2 is pivotally mounted in a bracket l4 fixed in any suitable manner to front face of the lay beam. The filling fork I2 is provided with tines 16 which are raised above the path of movement of the shuttle. The fork I2 is raised positively by a reciprocating cam or cam member [8 but is lowered, after the shuttle has passed, by gravity assisted by a spring (not shown). The filling fork described above is old and well known in the art.

The parts of the mechanism for raising the filling fork 12 includes a bell crank lever (not shown) which is rocked in one direction by a cam mechanism shown and described in the above mentioned Letters Patent. An actuating rod 20 is connected to the bell crank lever at one end and at its other end is mounted for reciprocating movement in an opening formed in t he lower end portion of the bracket I 4; The rod 20 carries the fork lifting cam l8 referred to above. The cam I8 is fixed to the rod 20 by suitable set screws 22 and is provided with a cam surface 24. 24 which is interrupted by a stop shoulder 26. The rod 20 is moved to the left by the bell crank lever hereinbefore referred to and the rod 20 is moved in the opposite direction by a spring (not shown). Thus, if the filling fork I2 is free to move downwardly because of filling failure, the arm 28 fixed to the filling fork will enter behind the stop 26 and prevent further movement of the rod 20 and effect stoppage of the loom in the manner described in the above mentioned Letters Patent.

The cam surface 24 and the arm 28 must be positioned very accurately relatively to each other to insure proper operation of the stop mechanism. Vibration of the rod 20 under some conditions may also be sufficient to cause rotation thereof and thus prevent the arm 28 from remaining behind the stop 26 thus permitting the rod 20 to continue its movement toward the right even though there has been filling failure. It is not practical to provide guides for the rod 20 since the rod not only moves lengthwise but also widthwise under the action of the bell crank lever referred to above.

The present invention provides a guide 30 for the rod 20 which is effective to prevent vibration thereof and also permits lengthwise and widthwise movement of the rod 20. The guide 30 is provided with an opening 32 arranged to receive the rod 20 and in which the rod is locked by a set screw 34. The guide is provided with a depending or lower end portion 36 which bears against the front surface of the lay plate 38. The guide 30 is also provided with an upwardly extending portion 40 having a threaded opening in its upper end for receiving a screw threaded stop member 42. The member 42 is provided with an enlarged head 44 which is arranged to bear against a plate 48 fixed to the front of the lay ID by suitable screws 48. The plate 46 is somewhat longer than the length of travel of the rod 20 to insure that the head 44 will remain in engagement with the plate 46 at all times. The stop member 42 is locked in adjusted position by a lock nut 50.

The guide 30 is fixed in position of the rod 20 by tightening the set screw 34 and causing the lower end portion 35 of the guide to bear against the front surface of the lay plate 38. The end portion 36 bears against the lay plate lay, a center filling fork, a longitudinally moving actuating rod, a fork liftin cam fixed to said rod and having a cam portion for lifting said fork when the rod is moved in one direction and a stop portion for cooperating with the fork to prevent movement of the rod in the other direction upon filling failure, and a guide member fixed to said rod and having oppositely disposed end portions bearing against said lay to prevent rotation of said rod during longitudinal movement thereof.

3. In a center fork stop motion for looms, a

' lay, a center filling fork, a longitudinally moving with only light pressure which is not sufficient to perceptibly flex the rod 20. The stop screw 42 is then adjusted until the hardened head 44 bears lightly against the wear plate 46. The pressure exerted by the stop screw 42 is sufficient slightly to flex the rod Zil and thus prevent undesired vibration of the rod 20 but the pressure exerted by the stop screw is not suflicient to prevent the rod 20 from moving freely in either direction under the influence of either the bell crank lever or the spring above referred to.

Having thus described my invention What I claim as new and desire to secure by, Letters Patent of the United States is:

1. In a center fork stop motion for looms, a lay, a center filling fork, a longitudinally moving actuating rod, a fork lifting cam fixed to said rod and having a cam portion for lifting said fork when the rod is moved in one direction and a stop portion for cooperating with the fork to prevent movement of the rod in the other direction upon filling failure, and a guide member fixed to said rod and bearing against said lay to prevent rotation of the rod during longitudinal movement thereof.

2. In a center fork stop motion for looms, a

actuating rod, a fork lifting cam fixed to said rod and having a cam portion for lifting said fork when the rod is moved in one direction and a stop portion for cooperating with the fork to prevent movement of the rod in the other direction upon filling failure, and a guide member having a portion surrounding and fixed to said rod and having oppositely extending end portions bearing against the front surface of the lay to prevent rotation of said rod during longitudinal movement thereof.

4. In a center fork stop motion for looms, a lay, a center filling fork, a longitudinally moving actuating rod, a fork lifting cam fixed to said rod and having a cam portion for lifting said fork when the rod is moved in one direction and a stop portion for cooperating with the fork to 

